1. Field of the Invention
This invention pertains to an apparatus for improving the performance of nightlights by providing a longer lighting life and higher efficacy. More particularly, the invention relates to improving nightlight performance by replacing a standard incandescent miniature lamp found in conventional nightlights with a light emitting diode (LED).
2. Discussion of the Art
Conventional nightlights often utilize miniature incandescent lamps as a light source. Incandescent lamps are generally fragile and have a relatively short operating life, thereby giving users the trouble of frequently replacing a failed bulb. Furthermore, filament lamps are not the most economical light source. These lamps have numerous components making them relatively expensive to manufacture and have a relatively high power consumption-to-light output ratio.
Light Emitting Diodes (LEDs) have made significant advances in providing a higher performing light source since their inception in the 1960""s. In the 1980""s, red-emitting AlGaAs LEDs were developed with external quantum efficiencies greater than 10%, such devices being more energy efficient and longer lasting producers of red light than red-filtered incandescent bulbs. As a result, LEDs have become cost effective replacements for standard incandescent light sources in various applications, such as automotive brake lights. Moreover, high-efficiency LEDs have been developed and are commercially available in the blue and blue/green wavelength range based on the InGaN and AlGaN material systems. Most recently, LEDs have been developed in the green and yellow color range with an external quantum efficiency greater than 1%.
The advent of UV and blue LEDs allowed the possibility to generate white light from an LED by applying luminescent phosphor materials on top of the LED. This layer of phosphor partially transforms the UV or blue light into longer wavelengths, e.g. yellow light. Successful implementation of such a device is dependent upon the efficient conversion of UV/blue light into visible light of the desired wavelength and the subsequent efficient extraction of the generated visible light from the device. However, the first commercially available white light LED systems were not competitive with standard light sources with respect to performance since the phosphor layer only partially transformed the UV or blue light into longer wavelengths. Not until recently have devices and methods been developed for efficiently converting UV/blue light into visible light. A detailed disclosure of a UV/blue LED-Phosphor Device with efficient conversion of UV/blue Light to visible light may be found in U.S. Pat. No. 5,813,752 (Singer) and U.S. Pat. No. 5,813,753 (Vriens).
White-light LED systems provide significant benefits over traditional incandescent lamps. As white light producing LED systems become more refined and efficient, a need exists to expand the use of such systems into others areas, such as the art of night-lights. As discussed above, the current incandescent lamps used for nightlights have various drawbacks. Constructing a nightlight with an LED as its light source would alleviate most, if not all, of the foregoing problems. To date, no device exists which adequately utilizes an LED system in nightlights. Therefore, it would be advantageous to provide an LED light source for nightlights which replaces the traditional filament lamp with an LED light source.
A new and improved apparatus is provided for improving the performance of nightlight systems by replacing the miniature incandescent lamps found in conventional nightlights with a light emitting diode.
A nightlight assembly includes a housing. A protective cover encloses at least a portion of the housing. At least one light emitting diode (LED) is mounted within the housing, which generates an LED beam and serves as the light source for the nightlight.
A nightlight assembly includes a wall plate adapted to fit over a switch plate extending from a substantially planar surface. The wall plate engages and abuts the substantially planar surface upon mounting the nightlight in its final operating position. At least one light emitting diode (LED) is mounted within the wall plate which serves as the light source for the nightlight.
One advantage of the present invention is the provision of a nightlight having a longer life and increased reliability.
Another advantage of the present invention resides in the reduced cost of manufacturing a nightlight due to the decreased number of required components.
Another advantage of the present invention is the ability to more precisely control light emitted from the nightlight.
Another advantage of the present invention is the provision of a nightlight having a minimal cost of operation due to the inherently low power consumption of the nightlight.
Yet another advantage of the present invention is the provision of a switch coupled to a variable resistor which allows control over the intensity of optical output and the number of LEDs in operation.
Yet another advantage of the present invention is the provision of a battery-powered nightlight which allows for a more desirable placement of the nightlight.
Still other benefits and advantages of the invention will become apparent to those skilled in the art upon a reading and understanding of the following detailed specification.